1. Field of the Invention
This invention relates generally to landing lights for aircraft, and more particularly to a covert landing light that provides illumination to aid pilots during takeoffs and landings without betraying the location of the aircraft.
2. Description of Related Art
Aircraft such as airplanes generally have landing lights mounted thereon for providing illumination to aid pilots during takeoffs and landings at night or when visibility is otherwise reduced. In a standard aircraft, these landing lights are typically provided by incandescent parabolic aluminized reflector (PAR) lamps that are plainly visible to anyone within sight of the aircraft. An example of this structure is shown in Petrick, U.S. Pat. No. 6,439,752 B1, hereby incorporated by reference in its entirety.
Such lamps are not suitable, however, to military aircraft that are operating in potentially hostile territory, because the lamps illuminate the aircraft and make it an easy target for attack. There is therefore a need for a covert landing lamp that assists the pilot of the aircraft with takeoffs and landings without betraying the location of the aircraft to potential enemies.
Prior art covert landing lights utilize infrared landing lights that cannot be seen by the human eye without external viewing aids such as night vision devices (e.g., night vision goggles). Infrared landing lights have been installed on military aircraft, and pilots aided by night vision devices are able to perform covert aircraft landings and takeoffs at night using infrared landing lights.
Known infrared landing lights include glass infrared filters placed in front of standard landing light fixtures. Two major problems exist with these known infrared landing lights. First, the known infrared landing lights “leak” light while in operation, allowing the aircraft to be seen by viewers in the vicinity. Second, the heat generated within the glass infrared filters causes the filters to crack and break. When this happens, the landing lights produce substantial amounts of visible light that render the pilots' night vision devices inoperable. Not only are the pilots temporarily blinded, but the substantial amounts of visible light produced allow the aircraft to be easily spotted by unaided viewers in the vicinity.
It would be beneficial to have an infrared landing light that produces very little visible light, thereby providing a high level of covertness, and is durable and dependable.